Swimming has grown as an important competitive sport. It has also grown as a very important fitness tool for thousands of others. Walk into any competitive or fitness pool and you will see at least one and sometimes up to as many as seven clocks fixed to the wall or mobile clocks on the deck area. These clocks are used for pacing and timing during swim training.
Competitive and fitness training has evolved considerably. Today, interval training is the basic tool of the swimmer's development and requires the swimmer to keep track of his/her time so that s/he can vary the intensity within pre-designed training sets. The current timing situation requires the swimmer to attempt to view the wall/deck clock resulting in a pause in stroke.
In distance training or competition, the swimmer must be able to pace his/herself to be most effective. Currently, the swimmer must pause and sight an on deck clock or simply trust his own inner timing. The end result is often a swim for a distance that is concluded with a surplus of energy or the opposite.